1. Field
The following description relates to a method of caching a content by a node and a method of transmitting a content by a content provider in a content-centric network (CCN).
2. Description of Related Art
A content-centric network (CCN) technique focuses on data rather than a location from which the data is to be retrieved, and thus, specifies a name of a content in a header of a packet, in contrast to an Internet Protocol (IP)-based network technique in which source and destination addresses are described in a header of a packet. Each router sets up a routing table, and using the routing table, a packet is forwarded to a location in which a content is present by referring to a header of the packet indicating a name of the content. In addition to the router, each network device includes a storage configured to temporarily store contents.
In a CCN, a packet is classified into a content request packet and a content reply packet. The content request packet includes a name of a requested content, and the content reply packet includes the requested content and the name of the requested content. When a content request packet is transmitted to a network device, the network device checks its storage for a corresponding content by a name of the content included in a header of the packet, and when the corresponding content is present in the storage, the network device sends a reply to the request by transmitting the content to a requester.
In a CCN, a node in which a requested content is present in a storage may send a reply to a request even though the node is an intermediate node. Accordingly, an average transmission path length is shortened, while eliminating a need for a content to be retrieved from an original content owner, resulting in a reduction of a total amount of network usage.